Archive for 01/01/2013 - 02/01/2013

Getting used to looking at one color can lead you to perceive an entirely different color.

Stare at the eye of the red parrot while you slowly count to 20, then immediately look at one spot in the empty birdcage. The faint, ghostly image of a blue-green bird should appear in the cage.

Try the same thing with the green cardinal, and a faint magenta bird should appear.

The ghostly birds are called afterimages. An after image is an image that stays with you even after you have stopped looking at something. As you stare at the red bird, light-sensitive cells at the back of your eyes become less responsive to red light. When you shift your gaze to the birdcage, your visual system “subtracts” red light from the white light that’s being reflected from the white background. White light minus red light is blue-green light. That’s why the afterimage of the parrot is blue-green. A similar thing happens when you stare at the green bird, but this time your eyes become less responsive to green light. White light minus green light is magenta light, so you see the afterimage as a magenta cardinal.

This is similar to few other optical illusion which i have posted earlier, check few other moving illusions here. Just move your eyes from one side to another and you will see the wheels moving. No circle is moving but at same time every single circle is moving, there are 5 circle in total, expect the you staring at all the circle will start moving and when you switch your sight to other circle, the other circle will stop moving, this will happen with all the circle you staring at.

Do you see a pattern of large and small squares? The apparent neon squares seem to pulsate slightly when we concentrate on the image...
This illusion combines 'neon color spreading' with 'illusory contour' effect: not only do you perceive squares where NONE exist, but the squares have also phantom colors!